If water is split using electrolysis, and the gases are collected, we find that there is twice the volume of hydrogen compared to oxygen. In my mind then, I see hydrogen as occupying two thirds of water with oxygen making up the other third. Water therefore, should read something like 66.66% hydrogen, right? Wrong. Apparently. I've chanced upon the Catholic Encyclopedia, and I wonder what they think about all this:
Water is an example of a compound substance, or chemical compound. Its molecule contains three atoms, two atoms of hydrogen, and one atom of oxygen. If a quantity of these two elements were mixed, the result would be a mechanical mixture of the molecules of the two. But if heat, or some other adequate cause were made to act, chemical action would follow and the molecules, splitting up, would combine atom with atom. Part of a molecule of oxygen--one atom--would combine with part of two atoms of hydrogen--two atoms. The result would be the production of a quantity of molecules of water. Each water molecule contains one atom of oxygen and two atoms of hydrogen.
Okay, I'm with it so far. Two parts hydrogen to one part oxygen. That's still two thirds hydrogen, right? Uhm... wrong.
The invariability of composition by weight of chemical compounds is a fundamental law of chemistry. Thus water under all circumstances consists of 88.88% of oxygen and 11.11% of hydrogen. This establishes a relation between the weights of the atoms of hydrogen and oxygen in the water molecule, which is 1:8.
What? 11.11% hydrogen? 1:8? What? Where did I go so horribly wrong? Let's take it from the top again and try to see where I took a nose-dive.
Oxygen and hydrogen are gaseous under ordinary conditions. If water is decomposed, and the vases collected and measured, there will always be two volumes of hydrogen to one of oxygen. This illustrates another fundamental law--the invariability of composition by gaseous volume of chemical compounds. From the composition by volume of water its molecule is taken as composed of two atoms of hydrogen and one of oxygen, on the assumption that in a given volume of any gas there is the same number of molecules. As there are two atoms in the molecules of both of these elements, the above may be put in a more popular way thus: the atoms of hydrogen and oxygen occupy the same space. The ratio spoken of above of 1:8, is therefore the ratio of two atoms of hydrogen to one of oxygen.
And there's more ...
It follows that the ratio of one atom of hydrogen to one atom of oxygen is 1:16. The numbers 1 and 16 thus determined, are the atomic weights of hydrogen and oxygen respectively. Strictly speaking they are not weights at all only numbers expressing the relation of weight. Atomic weights are determined for all the elements, based on several considerations, such as those outlined for the atoms of oxygen and hydrogen. Thus the term atom indicates not only the constituents of molecules but has a quantitative meaning, the proportional part of the element which enters into compounds.
The sum of the weights of the atoms in a molecule is the molecular weight of the substance. Thus the molecular weight of water is the sum of the weights of two hydrogen atoms, which is two, and of one oxygen atom, which is sixteen, a total of eighteen. If we divide the molecular weight of a compound into atomic weight of the atoms of any element in its molecule, it will give the proportion of the element in the compound. Taking water again, if we divide the molecular weight, 18, into the weight of the atoms of hydrogen in its molecule, 2, we obtain the fraction 2/18, which express the proportion of hydrogen in water. The same process gives the proportion of oxygen in water as 16/18.
http://www.newadvent.org/cathen/02051c.htm
Being something of an obstinate soul, this still doesn't make sense to me. 16/18 of oxygen in water? In the vases which collected the gases from the decomposition of water, we find twice the volume of hydrogen to oxygen, and not 1/9. I'm banging my head on my desk and it's still not making any sense (which is a shame cos' it normally works).
What is telling is where it states the "assumption that in a given volume of any gas there is the same number of molecules." I'm always suspicious of assumptions. I like to question assumptions. I like to turn assumptions upside-down and shake them. I like to put assumptions in a sack and then throw them over bridges. Oh no - there's no tea and crumpets for any assumptions in my house. I could go on but I'll save you the agony.
Early experimenters knew that in equal volumes, oxygen weighs sixteen times more than hydrogen. Referring to current theory, I don't think this necessarily means there is sixteen more times more oxygen than hydrogen in water. I think that there is one volume of oxygen, and two volumes of hydrogen.
In 1808 Joseph Louis Gay-Lussac, a master of experimental chemistry, was experimenting with the proportions of oxygen and hydrogen needed to make water. He found that combining volumes of hydrogen and oxygen to make water are almost exactly 2:1 (within 0.1%). For example, 2 litres of hydrogen would react with exactly 1 litre of oxygen, with no hydrogen or oxygen left over. Just to confuse things a little, if we were to perform this reaction we would find that it would give us only 2 litres of water, and not 3 litres as one might expect.
John Dalton (c.1810) began to assign atomic weights to the elements. By experimentation he found that to form water one gram of hydrogen always reacts with approximately eight grams of oxygen. Oxygen, Dalton deduced, has eight times the mass of hydrogen in water. At this stage, Dalton assumed that the number of atoms was the same for the two different quantities of gas. Basically one hydrogen atom was matched to one oxygen atom to make one water molecule (H-O). He therefore assumed one hydrogen atom to be twice as big as one oxygen atom.
The Italian physicist Avogadro didn't like Dalton's assumption - so he came up with his own one! In 1811, Avogadro proposed a theory where the same volume for any gas contained the same number of atoms. That is, one unit of hydrogen contains the same number of atoms as one unit of oxygen - or any other gas for that matter. 1 cm cubed of any gas at room temperature will contain about 25, 000, 000, 000, 000, 000, 000 particles.
Avogadro's number has washed over the essential differences between the size of atoms. Previously, Newton had thought that the atoms of gas were large, elastic objects, essentially filling space, and of different sizes for different atoms. Just to clarify, I tend to find myself using Newton's model of the universe. I distrust the kinetic theory of atoms. I don't think atoms are bouncing and whizzing all over the place. I think atoms are spinning, but they remain stationary - a bit like the wheels of a gym-bike! I think that atoms being different sizes might go some way in explaining how we get different EMR wavelengths.
Avogadro reasoned that if the number of atoms are the same, then an atom of oxygen must weigh sixteen times more than one atom of hydrogen. Avogadro then had to explain why two volumes of hydrogen added to one volume of oxygen gives us only two volumes of water, and not three. Where has the missing volume from the total disappeared to?
Avogadro "solves" this problem by slashing everything in half. In a water molecule we no longer have Dalton's hydrogen atom that is twice the size of the oxygen atom, we now have two hydrogen atoms to one oxygen atom - therefore making the formula of water H2O. Avogrado determines that there are the same number of atoms in a half unit of hydrogen as in eight units of oxygen. The implications of this are phenomenal - Avogadro has inadvertently split the atom!
I might be making too bold a statement here, but there appears to be no real basis for having diatomic oxygen or diatomic hydrogen, other than it being something which Avogadro took a fancy to. Avogadro's Law has no doubt aided chemists in quantifying their experiments, and their calculations, but the implications go so much further than the bounds of science. I don't think I exaggerate when I say that Avogadro's assumption has not only affected everything we see in science books, but has also gone on to shape and fashion our everyday perception of the world around us.
It pays to remember that oxygen weighs 16 times more than hydrogen. The Periodic Table shows hydrogen with an atomic number of 1, and oxygen at number 8. These are half unit values, and I think that this only incites further confusion. There is no ratio of 1:8, not really, except when applied to water vapour. According to weight, hydrogen has a value of 1, and oxygen has a value of 16, so I would prefer to maintain the ratio of 1:16.
On the Periodic Table, hydrogen is shown as atomic number one but is best described as being only half an atom. According to the Periodic Table, a hydrogen atom needs to be paired with another hydrogen atom to become a diatomic molecule. Only then does hydrogen become a complete atom. This pushes the atomic weight of hydrogen gas upto 2, when essentially, before Avogadro, the atomic weight of hydrogen gas was 1. This would therefore make the atomic weight of water 17, and not 18!
There now surfaces a certain irony that the word atom comes from the Greek "atomos", meaning "indivisible". But atoms, being something supposedly indivisible, were divided so that an anomaly in our understanding of the structure of water, and ultimately the Universe, could be pushed to one side. Can you indulge me a little, and try to accept that from here on in, that when I say hydrogen atom I am referring to a complete hydrogen gas particle? A hydrogen atom, poised at atomic number 1, is now complete with two electrons acting as dipolar vortices, and the hydrogen atom manages to remain a toroidal structure.
Hydrogen is a basic building block of galaxies, stars and nebulae. It is consumed in the furnaces at the cores of stars and converted into helium, and subsequently heavier elements such as carbon, oxygen and nitrogen - the basic building blocks of life. I'm over-simplifying nucleosynthesis here but basically one hydrogen atom plus another hydrogen atom, under the right conditions, makes one helium atom. In theory then, it takes 16 hydrogen molecules to make one oxygen molecule.
If I were to take an ordinary pint glass and fill one third of it with builders sand, and then fill-in the rest with rolled-up bits of tissue paper, and I was asked to describe what I was seeing, then I would say that there was one third sand and two thirds tissue paper in the glass. If I was to base my description strictly on weight, then I might find myself saying that there was mostly sand, and barely any tissue paper in the glass - which isn't exactly true is it?
There has been a previous post I made on this blog called "Rocks and Sand". In it I describe how 50 ml of water added to 50 ml of ethanol, does not give you 100 ml of solution, but rather something around 98 ml. 2 ml have disappeared! The analogy was that if we have a box full of basket balls representing the ethanol, and then we pour marbles which represent water into the box, we find that the marbles are filling the spaces between the basket balls, and this is how some of the volume goes missing - it's a gap filler. Can this analogy in any way be applied to what we are seeing happen to hydrogen and oxygen as they form water vapour?
The oxygen atom is basically 16 times more dense than the hydrogen atom. Water is formed by the weight ratio of 8 to 1. 8 grams of oxygen will form water with 1 gram of hydrogen. Dalton suggested that hydrogen atoms were twice the size of the oxygen atom. Is it possible that under the reaction to make water vapour that the oxygen atoms fill the spaces between the hydrogen atoms?
Another possible scenario is that in making water vapour the atoms shrink in volume. The hydrogen atom, atomic number 1, occupies 2 units, and that the oxygen atom, atomic number 16, occupies 1 unit. If the hydrogen is combusted, then the resulting steam occupies 2 units, and has an atomic number of 17. Let's imagine then that our humble hydrogen atom has shrunk to half its size. The hydrogen atom no longer occupies 2 units, but only one unit. If we add this to the one unit that the oxygen atom occupies, then we have a total volume of 2 units. This might help explain why we find steam occupies only 2 units.
So instead of dividing the hydrogen atom in half as Avogadro did, we have merely reduced it's volume. Thus, in water we now have one unit of hydrogen and one unit of oxygen. Does that mean therefore that water is made up 50/50 of hydrogen/oxygen atoms?
I'm thinking how an atom might reduce its size. Remember, it is the hydrogen which is burnt to make water. The reaction could make the hydrogen atom spin faster. In the same way that an ice-skater spins faster if they pull their leg in, then the effect could be applied to a spinning atom. Under the constant applied pressure of the aether, an atom with a smaller circumference would spin faster.
Which leads us to something pretty interesting. We are told that hydrogen gas doesn't exist as a gas here on Earth. We have to seperate hydrogen atoms from water, biomass, or natural gas molecules (the two most common methods for producing hydrogen are steam reforming and electrolysis).
If we were to heat up a small amount of water in a metal container, the water would turn into steam. Pouring cold water over the container would condense the steam back into water. The can also implodes, and looks like its been sucked-in from the inside. Condensation pulls a vacuum. It's intriguing that the steam occupies a volume which is some 1700 times greater than the water.
The new atomic weight of water is 17, that is one hydrogen atom which has the value of 1 in weight, being joined by an oxygen atom which has the value of 16, to give us a total of 17.
I'm very excited. This opens up whole avenues to explore. There's a whole Universe to look at in a different way now. There is one thing bugging me though. Hydrogen is now restored as a complete atom, with the atomic number of 1. The oxygen atom, in its complete state, now occupies the atomic number 16. That is pushing sulphur out of the number 16 slot. It appears that perhaps sulphur does not belong at number 16. And also, what happens to the number 8 slot now that oxygen has vocated it?
And you know what? My head's finally stopped hurting... only until I start thinking about it again.
Many thanks:
A dictionary of chemistry ... By Andrew Ure
http://www.krysstal.com/reactions.html
http://www.eia.doe.gov/kids/energyfacts/sources/IntermediateHydrogen.html
http://www.theweatherprediction.com/habyhints/260/
http://www.woodrow.org/teachers/ci/faraday/lab3.html
http://www.visionlearning.com/library/module_viewer.php?mid=49
http://science.jrank.org/pages/634/Atomic-Weight-History.html
http://www.coolscience.org/CoolScience/KidScientists/H2O2Balloons.htm
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